Work driver



Mar. 20, 1923. 1,449,126

F. MULLER WORK DRIVER Filed Jan. 28, 1920 Patented Mar. 20, 1923.

UNITED STATES PATENT OFFICE.

FRIEDlllRICH MTl'LLER, OF HARTFORD, CONNECTICUT, ASSIGNOR TO PRATT & WHIT- NEY COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

WORK DRIVER.

Application filed January 28, 1920.

1/ all whom it may concern a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in l Vork Drivers, of which the following is a specification.

This invention relates to a work driver of the rotary floating chuck type such as shown in my Patent No. 1,187,920 granted June th, 1916, and it is the general obj ect of the invention to provide an improved chuck of this character.

It is a further object of the invention to provide an improved work driving chuck which will be more compact and rigid than like devices heretofore used, and the exterior contour and appearance of which will be greatly improved.

It is another object of the invention to provide a new and improved type of auxiliary work driving jaw which will grip the work more securely, such type of jaw being adapted for neralwork driving use.

It is still a turther object of the invention to provide means for normally holding the jaw-supporting member in a position central ot the chuck or work driver, such means, however, in no way hinderingthe floating action. of the chuck.

With the above and other objects in view as will hereinafter appear, the invention will now be described by reference to the drawing, wherein.

Figure 1 is longitudinal section of the improved work driver taken on the line l-l of Fig. 2.

Fig. 2 is a front elevation of the same. showing a portion of he faceplate broken away, one of the work driving jaws removed, and another jaw in section.

Fig. 3 is a cross section taken on line of Fig. 1.

Fig. 4 is a fragmentary side elevation of the front of the work driver to more clearly illustrate the manner of mounting the work driving jaws.

Fig. 5 is an enlarged diagrammatic side elevation oiione of the auxiliary jaw members, the work and portions oi the other Serial No. 354,755.

cooperating jaw members also being illustrated.

is in my patent above mentioned, I have herein illustrated my invention as applied to the spindle l of a lathe, although it will be. iuiderstood that the invention is in no way limited thereto. The work driver comprising the invention is composed broadly of four elements; namely, the driving member 2, the floating driven member 3, the work driving jaws 4c and. the cam ring mechanism 5. The driven member 3 is oatinglv mounted on the driving member 'n such manner as to be driven thereby. l: prefer to provide the driven member 3 with a peripheral flange 6 and to notchthe flange at one or more places to receive a projectionor projections on the driving inei'nber. in the drawing 1 have shown two such projections 7 and a like number of notches in the said flange for receiving such projections. The engagement of these members is sutliciently loose to allow a lateral movement or play of the floating member. but the construction is such that the members are in driving contact at all times. The floating driven member 3 is adapted to support the work driving jaws i which are preferably radially slidably mounted on the member itseli or on means supported. thereby. I preferably provide a disk-like member 8 which I secure to the floating member by proper means, such as bolts 9. such member 8 being provided with ways 10 to receive the work driving jaws. This member. which is broadly considered part of the floating member, vith the rk driving jaws therein forms the trout face pl e of the chuck. The jaws and ways are ormed with corresponding guide ribs and grooves ll whereovthejaws are rigidly held entirely within the outline of the chzu'k and secured from any lateral movement.

Mounted on the driving member 2 and surrounding the driven member 3 is the cam ring mechanism This mechanism comprises base member 12 mounted on the driving member and'provided with a cylindrical flange 13 and a cam plate or ring 1 having a like flange mounted on the flange of the base member and secured by any proper means as by screws 15. This cam ring mechanism is adapted to normally hold the work driving jaws in a closed position, such operation preferably being accomplished by the following mechanism. A spiral spring 16 having one end secured to the cam ring at 17 and the otherend secured to the floating driven member 3 at 18 tends to normally rotate the cam ring in the direction indicated the inner end 18 of the spring 16 being held from any appreciable rotation relative to the spindle 1, the outer end 17 of the spring will tend to rotate the cam ring in a jawclosing direction (indicated by the arrow, Fig. 2) and thereby normally keep the jaws in a closed position.

.As heretofore stated, I provide a novel and improved type of work-engaging jaw 22 which while being of particular advantage in a work driver of the present type is in no way limited thereto but is adapted to general use. The peculiar form of the work-engaging portion of this jaw renders it particularly useful in rigidly securing work in place whether such work is to be secured to a work table or to be held rotatably as in the present construction. I have illustrated this jaw in detail in Fig. 5 of the drawing and in Figs. 1 and 2 l have shown the same as applied to a work driver of the type herein disclosed.

Any convenient form of auxiliary work-em gaging jaw may be used with my improved chuck but in order to more securely hold and drive the work, I prefer to use the novel ly increasing pitch.

auxiliary jaw 22 which I mount in the workengaging end of each main jaw 4. As shown in Figs. 1, 2 and 5, each jaw 22 comprises a flat plate-like member having a pivot hole 23 and a spiral-like periphery 2 1 of progressive- I may form such jaw with a work-engaging periphery having stepped spiral portions of progressively increasing pitch or such jaw may be formed with a non-stepped spiral-like periphery gradually and continuously increasing in pitch if desired. This construction will be more clearly understood by reference to Fig. 5 wherein I have illustrated the jaw as having three of the said stepped portions. As

shown in Figs. 2 and 5, the work W is initially engaged at the point a on each jaw 22, the path aZ) in Fig. 5 preferably being While I have herein shown the jaw as pro-' vided with three stepped portions yet it will be readily understood that any desired number may be formed on' each jaw. Each jaw 22 is provided with means for vnormally holding the lowest work-engaging portion a thereof in workengaging position. Such means herein comprises a plunger 25 seated in the main jaw and normally pressed outward against a projection 26 on the auxiliary jaw by means of a compression spring 27. In operation the jaws initially engage the work as shown in Figs. 2 and 5 with the lowest spiral portion a in direct contact with the work. direction of the arrow, Fig. 2, the drag of the work on the peripheries of the jaws 22 will rotate such jaws about their pivots 2.3 in the direction of the arrow in Fig. 5. This action will tightly grip the work within the three jaws and the greater the work-rotating torsion. the tighter will be the grip of the jaws. It should be noted that as each jaw 22 rotates to the left, Fig. 5, in engaging the work, a steeper work-engaging spiral successively comes into contact with the work. In this construction the, work is initially engaged at a and as the chuck is rotated, a rolling contact between the work and the gradually rising peripheral portion (a -Z1 takes place, thereby tightly wedging the work within the jaws. As soon as the work is wedged tightly within the jaws, it is de-' sirable that the rolling action of the jaws on the work should cease and that the jaws should rotate the work. The path Z)-0 is steeper in pitch. than the path ab and therefore the wedging action on the work will be greater at such portion b-c, such action tending td prevent further rolling contact of the jaws on the work and to rotate the work. The path c-(Z is steeper in pitch than the path 7)c and should the work pass over the portion ?)-0, it will be engaged by this steeper pitch to stop the rolling contact and to rotate the work.

As stated above, and as shown in my aforesaid patent, the jaw-supporting member 3 is loosely or floatingly mounted on the driving member 2. This construction permits the jaws to adjust themselves to the work even though the latter is not exactly concentric to the center 28 on the spindle 1; When the jaws are not engaged with the work or when As the chuck is rotated in the llO work is being inserted into the chuck, it is desirable that the floating member and jaws be held in a central position in the chuck. I provide means for performing this function, such means being herein illustrated a plurality of springs 29 secured to an element 30 within the floating member 3 and adapted to surround the center 28 of the spindle. As shown in Fig. 3, the outermost portions of such springs engage the interior of the floating member and normally hold the same in a central position in such manner that work may easily be inserted therein. Also when the chuck is removed from the spindle, the springs 29 keep the element centered in such manner that it may be easily reengaged on the center 28. It should be noted that these springs are not strong enough to interfere with the lat eral movement of the floating member whereby the jaws are allowed to adapt themselves to the contour of the work.

Upon the inner side of the base member 12 or the cam ring mechanisms are two proections or lugs 31, and these projections present a convenient means tc be engaged by a suitable intermittently operable device for arresting? the turning of the cam ring mechanism 5) with the driving member 3, and when this occurs the jaws 4 through the intermediate narts will be opened. There are, of course, other ways in which the motion of the cam ring n'iechanisn'i with re spect to the driven member might be arrested but the said projections in connection with a cooperating member, which 1 will hereinafter describe, answer satisfactorily in this connection,

Loosely mounted on the forward portion of the spindle l is a sleeve 32 provided at its forward end with an annular flange 83. Encircling and slldable on said sleeve is a ring and between said ring and flange '38 is a body oi suitable iric tional material such as leather, the ring 3d, frictional material 35 and flange being pressed together by one or more springs 36, seated in sockets 3'? in said ring 34s and bearing against the bottoms of the sockets andalso against a disk 38 surrounding the sleeve 32. The disk 38 is provided with one or more guide pins 39 which fit bores in the ring as to arevent turning of the said ring as the same is moved back and forth on the sleeve 32. llon-rotatably fitting the said sleeve is a collar 40 and between said collar and disk 558 is a body ll of frictional material. On the front face of the flange 33 are projections 42 cooperative with the projections 31. The two sets of projections are shown out of contact in Fig. l but it will be evident that when the projections 42 are moved into the path of the projections 31 the motion of the cam ring mechanism 5 with the driven inemher 3 will be arrested, when the projections 31 engage the projections 42 to effect the Opening oi: the jaws l. As a means for shifting the sleeve 32 the lever 4.3 may be utilized. 1 have not deemed it necessary to show the mounting of this lever and while it may be either operated by hand. or automatically, it will in the case of a lathe be operated automatically. The lever 43 is between the two and that one of these members turns with respect to the other. The ring 34k and disc 38 constitute together one of said members while the other is composed of the sleeve 32 and the collar 40, the sleeve 32 and collar 40 bein turnable with respect to said ring 34 and disk 38. The "frictional resistance exerted by the two washers 35 add 41 is greater than the force of the spring l6 so that when the projections 42 arrest the projections 31 in the manner already decribed, the aws l willbe fully opened, but when said jaws have been opened to their )5 xiinui'n extent and when the lugs 20 have encountered the end walls of the cam slots 19, the sleeve and collar 40 will slip on the leather vashers 35 and il and therefore turn with respect to the ring 34- and disk 38, the jaws 4 remaining open. It will be understood that the instant the projections -12 are moved out of engagement with the projections 31the jaws a will be closed by the spring 16.

l v hat l claim is:

l work driver comprising the combi nation or a driving member, a floating men:- ber adapted to be driven by said driving member, an element secured to the floating member and providing a front cover or face plate for the driver, a plurality of work driving jaws rectilinearly sli-dably mounted in said element. and mechanism for causing the opening and closing oi said jaws.

A work driv r comprising the conioination of a driving member, a floating member adapted to be driven by said driving memb cam plate. an elei'nent'secured to the floting member and providing a "front cover or face plate for the driver, a plurality 01: work driving jaws slidahly mounted in said element and having lugs eng g ing eccentric grooves in the cain plate, and mechanism for rotating the cam plates to open and close the jaws.

3. A work driver comprising the combination of a driving member, a floatinginember adapted to be driven by said driving member, a cam plate, an element secured to the floating member and providing a front cover or face plate for the driver, a plurality of work driving jaws slidably mounted in said element and having lugs engaging eecentric grooves in the cam plate, a spring for normally rotating the cam plate to close the jaws, and means for causing the opening of said jaws. I 4. A work driver comprising the combination of a driving member, a floating member adapted to be driven by said driving member, a plurality of work driving jaws rectilinearly slidably mounted in said float ing member, auxiliary jaws pivoted on the work driving jaws and provided with spiral-like work-engaging peripheries, spring means for normally holding the auxiliary jaws with the lowest portions of the peripheries in work-engaging position, and mech-.

" ani'sm for causing the-opening and closing ber adapted to be driven by said driving ing pltch.

of said work driving aws.

5. A work driver comprising the combination 01 adriving member, a floating memmember, a plurality of work driving jaws mounted 1n sald floatlng member, and an auxiliary jaw plvotally mounted on each work drivingjaw, each said auxiliaryjmv being provided-with a spiral-like work-em gaging periphery of progressively increas- 6. A work driver comprising the combination of a driving member, a floating member adapted to be driven by said driving member, work driving jaws mounted on said floating member, and means to normally center said floating ,meinb'er.

7 A work'driver comprising the combina' tion of a driving member, a floating member adapted to be driven by said driving member, work driving jaws mounted on said floating member, and spring means to normally center said floating member.

8. A work driver comprising the combination 01"- a driving member, a floating member adapted. to be driven by said driving member, work driving jaws mounted on said floating member, and a plurality of springs adapted to engage the interior of the float ing member to center the same. I

9. A work driver comprising the combination of a driving member, a floating member adapted to be driven by said driving member, a plurality of work driving jaws mounted on said floating member, an element with 4 in the floating member adapted to engage a carrier spindle, and spring means between the element and floating member vtor normally keeping such element and floating member in axial alinement.

10. A work driver having work-engaging means comprising a pivoted jaw, said' aw being provided with a periphery comprising work-engaging spiral stepped portions, each.

successive spiral thereof loeino of a steeper pitch. i

12. A work driver having work-engage ing means comprising the combination of a pivoted jaw and spring means engaging the jaw to normally hold the jaw in workengaging position, said jaw being provided With a spiral-like work-engaging periphery of progresslvely increasing pitch.

13. A work driver comprising the combination of a rotary chuck having three workengaging jaws pivotally supported thereby, said jaws each being provided with a spirallike work-engaging periphery of progressively increasing pitch.

14:. A work driver comprising the combi nation of a rotary chuck having three workengaging jaws pivotally supported thereby, and spring means for normally holding the jaws in work-engaging position, said jaws each being provided with a spiral-like workengaging periphery of progressively increasing pitch.

15. A work driver comprising the combination of a rotaryv chuck having three work driving aws radially slidably mounted therein, and a work-engaging jaw pivotally mounted on each work driving jaw, said work-engaging jaws each being provided with a spiral-like work-engaging periphery of progressively increasing p tch.

16. A work driver comprising the combination of a rotary chuck having three work driving jaws radially slidably mounted therein, a work-engaging jaw pivotally mounted on each work driving jaw, and mechanism for opening and closing the jaws radially while the chuck is rotating, said work-engaging jaws each being provided with a spiral-like workengaging periphery of progressively increasing pitch.

17. A work driving jaw having a pivot center and a spiral-like work-engaging pe-' riphery of progressively increasing pitch.

18. A work driving jaw having a pivot center and a.\vork-engaging periphery comprising spiral stepped portions, each successive spiral thereof being of a steeper pitch.

19. The combination of a work driving jaw having an auxiliary jaw mounted thereon, said auxiliary jaw being provided with a spiral-like work-engaging periphery of progressively increasing pitch.

20. The combination of a work driving jaw having an auxiliary jaw pivotally mounted thereon, said auxiliary jaw being provided with a periphery comprising workengaging spiral stepped portions, each anol spring-pressed means engaging the successive spiral thereof being 0i a steeper auxillary aw and normally holding the 10 pitch. lowest Work-engaging portion 01" its periph- 21. The co mbinatlon of a Work driving ery 1n work-engaging position.

5 having an auxiliary jaw piv0tally In testimony whereof, I hereto affix my mounted thereon, said auxiliary aw being signature. provided with aspiral-like Work-engaging periphery of progressively increasing pitch, FRIEDERICH MULLER. 

